The panel will examine reports of prison camps, torture and food deprivation, reporting back in March 2014, a UN statement said.

North Korea has previously denounced the investigation as a political ploy.

It is highly unlikely that North Korea will give access to the investigators, so the panel will have to rely on satellite imagery and testimony from defectors.

However, Michael Kirby, a former justice of Australia's High Court, said the panel would approach the inquiry with "complete independence" and no "preconceptions", and that North Korea would be given "due process".

"I certainly want to try to engage with North Korea so that we can get the best and most reliable material and report that to the United Nations which, after all, is the eyes and ears of the world," he told Australian broadcaster ABC.

Mr Kirby added that many people had already contacted him, offering to make submissions to the commission.

He will be joined by Sonja Biserko, a founder of the Helsinki Committee for Human Rights in Serbia, and former Indonesia attorney-general Marzuki Darusman.

Marzuki Darusman is currently the UN Special Rapporteur on North Korea. He had presented the UN's initial report on North Korea, which led the UN human rights council to set up the inquiry.

His report highlighted the conditions in North Korea's prison camps, believed to hold around 200,000 people, and described "widespread and systematic violations of human rights" including enforced disappearances and using food to control people.